In March, the first pieces of glazing that had begun installation on Kohn Pedersen Fox's huge China Zun Tower in Beijing. The following months have seen substantial progress on both cladding placement and floor assembly, as the supertall skyscraper for state-owned investment company CITIC rapidly rises towards its 528-metre pinnacle.

Beijing's tallest building continues to flaunt its excessive height, as recent photos sent to us by architect Kohn Pedersen Fox Associates highlight the supertall's striking curvature and textured cladding system. The China Zun Tower, also known as the CITIC Tower after its primary tenant, will climb to a height of 528 metres across 108 floors.

BEIJING—Construction at the top of the tallest building in China’s capital has stalled because of government security concerns, according to people involved in its design and construction, in a new example of how China’s passion for skyscrapers is cooling.

Government officials have halted work on the planned observation deck on China Zun Tower’s 106th floor because of concerns that visitors would be able to see into the compound where Communist Party leaders live and work, according to the people involved.

The security push goes beyond China Zun. The city said on Wednesday that it would limit the height of buildings in its center—offering no details but citing the need to “safeguard the security of the central-government environment.” The plan includes the district where China Zun sits . . .

. . . while China once gushed over trophy towers—including ones shaped like eggs, coins and teapots—that helped put its fast-growing megacities on the world map, their popularity has waned.

Mr. Xi in late 2014 issued a call to stop the construction of “strange-looking” buildings.